Increasing the atmosphere's carbon dioxide content from three parts per 10,000 (0.03%) to four parts per 10,000 (0.04%) should cause some modest global warming. However, the extremely cold winter reminds us this modest warming is not creating the worldwide climate catastrophe predicted by global warming activists. It also provides appropriate context for the next time we experience a heat wave and activists tell us global warming is to blame.

Cold spells, heat waves and extreme weather events will continue to occur as our planet modestly warms. This winter's extreme cold outbreaks illustrate that global warming is not changing our planet's climate severely, as activists claim. To the extent changes are occurring, these are benefiting rather than harming human health and welfare.

James M. Taylor is senior fellow for environment policy at The Heartland Institute, a Chicago think tank that promotes free-market policies.